1 .\" $NetBSD: ungetwc.3,v 1.7 2003/09/08 17:54:32 wiz Exp $
2 .\" $DragonFly: src/lib/libc/stdio/ungetwc.3,v 1.1 2005/07/25 00:37:41 joerg Exp $
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35 .\" @(#)ungetc.3 8.1 (Berkeley) 6/4/93
42 .Nd un-get wide-character from input stream
49 .Fn ungetwc "wint_t wc" "FILE *stream"
53 function pushes the wide-character
55 (converted to an wchar_t)
56 back onto the input stream pointed to by
58 The pushed-backed wide-characters will be returned by subsequent reads on the
59 stream (in reverse order).
60 A successful intervening call, using the same stream, to one of the file
66 will discard the pushed back wide-characters.
68 One wide-character of push-back is guaranteed,
69 but as long as there is
70 sufficient memory, an effectively infinite amount of pushback is allowed.
72 If a character is successfully pushed-back,
73 the end-of-file indicator for the stream is cleared.
79 the wide-character pushed-back after the conversion, or
81 if the operation fails.
82 If the value of the argument
86 the operation will fail and the stream will remain unchanged.
96 The current implementation uses a fixed sized ungetwc-buffer.